This invention relates to a network control device and method including network control software.
In recent years local area networks (LAN) for connecting computers together have become widespread. These type of local area networks are capable of connecting computers in the same floor of a building or the entire building, a group of buildings, a district or even larger areas and can even connect to networks on a worldwide scale. Each of these mutually connected local area networks (LAN) may utilize diverse hardware connection technology or a plurality of network protocol.
Other isolated local area networks (LAN) of simple structure can be supervised by individual users. In other words, the user can replace equipment, install software and diagnose problems.
However, large-scale complex LAN and large, mutually interconnected LAN groups require management referred to here as “Management”. This “Management” means both a person to act as the network administrator and the software used by the network administrator. In this document, the term “management” signifies control utilizing software to manage the entire system, and the term “user” signifies the person utilizing the network control software. The user usually acts as the system control administrator. The user can make use of the network control software to obtain control data on the network and change this data.
Large-scale network systems are usually required to be active systems that must constantly perform equipment expansion or removal, software updating and problem detection, etc. Generally, such systems are owned by various persons or exist as various systems supplied by various operators.
Several methods have been attempted with numerous standards systems as methods for controlling devices on networks comprising a large-scale network system. The International Standards Organization (ISO) has proposed a general-purpose standards framework called the Open System connection (OSI) model. The network control protocol for the OSI model is called the Common Management Information Protocol. The Common Management Information Protocol or CMIP is a common network control protocol from Europe.
Also from the USA, a network management protocol for greater common use is known as Simple Network Management Protocol (SNMP) which is a complete change from the CMIP associated with it. (See “Introduction to TCP/IP Network Management—For Practical Network Control” by M. T. Rose, translated by Takeshi Nishida, First edition Aug. 20. 1992 Toppan.)
This Simple Network Management Protocol has at least one network management station (NMS) in the network management system. Each station has a plurality of management nodes including agents, as well as a network protocol so that the management stations and agents can exchange management information. The user can therefore obtain data on the network and also make changes to this data by utilizing electronic communication (modem) and the agent software for the management node via this network management software on NMS (network management station).
The agent here, refers to the software running as a background process of the target devices. When the user requests management data for equipment on the network, the management software places the object identification information in a management packet frame and sends this object information to the target agent. The agent interprets this object identification information, extracts data corresponding to this object identification information, places this data back in the packet and sends this packet back to the user. In some cases, a process corresponding to the data that was extracted, may be called up.
This agent also maintains data regarding its own status in a data base configuration. This data base is called a Management Information Base (MIB)). FIG. 4 shows a concept view of the MIB configuration. As shown in FIG. 4, the MIB has a tree type data structure and all nodes are affixed with a number. The number inside the parentheses in FIG. 4 is an identifier for that node. For instance, the identifier for node 401 is “1”. The identifier for node 402 is a “3” under node 401 and therefore listed as “1•3”. In the same way, the identifier for node 403 is listed as “1•3•6•1•2”. The identifier for these nodes is known as the object identifier.
The structure of this MIB is called the Structure of Management Information (SMI) and conforms to the “RC1155 Structure and Identification of Management Information for TCP/IP-based Internets”.
Only a fraction of the MIB specified as a standard has been extracted and shown in FIG. 4.
In FIG. 4, the numeral 404 is a node representing the peak of the object group and referred to as a standard MIB provided as a standard feature in equipment managed by Simple Network Management Protocol (SNMP). The detailed structure of the objects ranked below this node are specified in “RFC1213 Management Information Base for Network Management of TCP/IP-based internets: MIB-II. The numeral 405 is anode at the peak of the object group called the printer MIB and is provided as a standard item in printers managed by Simple Network Management Protocol (SNMP). The detailed structure of the objects ranked below this node are specified in “RFC1759 Printer MIB. Further, the numeral 406 is referred to as a private MIB and is a peak node for defining autonomous MIB such as used by companies and organizations. The numeral 407 is called a company expansion MIB and is a peak node for autonomous expansion of a company within the private MIB. The Canon Corporation has been assigned “1602” as a company number for definition as an autonomous entity and the peak node 408 for defining Canon MIB which is a Canon autonomous MIB and “408” is ranked at a position below the node 407 which signifies companies. The object identifier “1•3•6•1•4•1•1602” is for the peak node of the Canon MIB.
However, on starting up the network management software, and acquiring all the MIB objects controlled by the network management software, a massive quantity of SNMP packets flow through the LAN at nearly the same time. This flow places a large burden on the channels and at the same time also places an extremely heavy load on the printer and the network boards that process those SNMP packets.
Also, along with this increased load, the startup of the network management software also requires more time (initial menu display) which causes the user to feel stressed.
Further, the network printer management software is constantly writing the MIB data with the same process sequence. Therefore, when the user directs the network printer software to write MIB data, the network printer software of the conventional art constantly writes all of. the directed MIB data. However writing all of the MIB data each time is not always necessary and the process is redundant. In other words, the network printer software generally displays a plurality of information for the user simultaneously (information matching the MIB data) and even if the user only rewrites just a fraction of all this information, all of the displayed information of the overwrite is processed as items specified by the user.
Among the MIB data specified for rewriting by the user, items for which write is requested from the network management software for SNMP agents on the network printer, represent only the MIB data actually rewritten by the user. There is therefore no need to request write via SNMP agents on the network printer of MIB data which the user has not rewritten. Not only is such writing unnecessary but reducing the quantity of MIB data subject to write request via SNMP agents on the network printer from the network printer management software is also essential in order to reduce the load (amount of work) assigned to the network traffic (data quantity) and the network printer.